FDA issues warning over painkiller Fentora

28 September, 2007

The United States Food and Drug Administration (FDA) has warned the public about the potential fatal risk associated with the improper use of painkiller drug Fentora, manufactured by Cephalon Incorporated.

The warning comes after Cephalon, the biopharmaceutical company based in the United States, warned doctors earlier in September 2007 about several patient deaths related to inappropriate prescribing of Fentora.

In its letter to health professionals on September 10, 2007, Cephalon said patient deaths were on account of improper patient selection, dosing, or product substitution. It also warned that Fentora should not be used as a replacement for a similar painkiller sold by Cephalon called Actiq.

Fentora delivers more medication to the blood than Actiq, and substituting the same dose for Actiq can be fatal, the FDA said.

Fentora is made from fentanyl, which in raw form is 80 times stronger than morphine. Cephalon officials said that, once fentanyl is processed, the difference is much less.

Fentora is approved only for treating pain in cancer patients who experience ‘breakthrough pain’ because they have developed tolerances to other opiate painkillers, such as morphine.

Breakthrough cancer pain is an intense increase in pain that occurs in bursts, with rapid onset even when pain-control medication is being used.

In its advisory, the FDA has cautioned against people taking Fentora for migraines or other types of short-term pain.

Doctors can prescribe drugs for uses outside their approved labeling, a practice known as “off-label use.” Many doctors prescribe Fentora off-label for headaches and back pain. Once a drug has been approved by the FDA, doctors are free to prescribe it as they deem fit.

The FDA said several Fentora-related deaths have occurred in patients who were prescribed the drug for off-label use.

It warned that Fentora should not be used for any other conditions. It should only be given to patients who have developed opiate tolerance, as others will not be able to handle the high amounts of fentanyl contained in Fentora.

The FDA also warned people taking Fentora and their caregivers to follow carefully the drug’s label directions. The agency advised that patients and caregivers become familiar with the signs of fentanyl overdose.

Cephalon Incorporated is now working with the FDA to update Fentora’s package insert to include revised patient selection criteria and dosing instructions.

The company has been testing the use of Fentora for other types of pain, and had announced in August 2007 that it expected to seek FDA approval for expanding the approved uses for the drug by the end of 2007.

In 2006, an inquiry by the attorney-general of Connecticut had found that Cephalon promoted some drugs for uses for which they were not approved, a practice that is illegal.

Dr Scott Fishman, former president of the American Academy of Pain Medicine and professor at the University of California in Davis, said a big issue is that doctors are not trained in pain management, especially with faster-acting painkillers like Actiq and Fentora.